Yarn knotter



s. FURST YARN KNOTTER April 25, 1951 5 Sheets-Sheet 1 Filed July l. 1959 April 25, 1961 s. FURsT 2,981,559

YARN KNOTTER Filed July l, 1959 5 Sheets-Sheet 2 April 25, 1961 Filed July 1, 1959 s. FU RST YARN KNOTTER 5 Sheets-Sheet I5 Located between the two tie beaks 26 and 27 is a forked tensioning member 17 having fork branches 17a and 17b (Figs. 14, 6-11). The tensioning member 17 is axially displaceable and can be shifted into a position Where the ends of fork branches 17a and 17h protrude toward the left (Fig. 14) beyond the location of the tie beaks.

The tensioning member 17 is driven byV means of a lever 28 (Fig. 14) pivoted at 28a and controlled by another Cam 3@ xedly mounted on the cam shaft 29. The tensioning member 17 is biased toward the right by means of a helical spring 31 positioned around the shaft and axially biased between pin 31a, fixed to the shaft of member 17, and abutment 31b in hollow shaft 21, thus urging member 17 to normally occupy the position shown in Fig. 14. The lever 28 engages the cam 30 through a cam follower provided with an adjustable set screw 41 which can be arrested in the proper desired position within a sleeve 43 by means of an adjustable collar or lock nut 42. The sleeve 43 is displaceably mounted in the lower end of the lever 2S and transmits its camfollower motion through a helical compression spring 44 on tothe lever 28 in whose bore 45 the sleeve 43 can freely glide during compression of the spring 44. The yarn knotting operation takes place as follows. The end portions a and b of the two yarn lengths to be tied together are rst so positioned in readiness that the ends 'c and d point in different directions (Fig.,1).

This may be. accomplished by seizing and positioning devices operating, for example, by suction and which are well known in the art of textile winding machines. The yarn pieces a and b pass into the bight of the adjacent beaks 26 and 27 respectively. Now the cam shaft 29 (Fig. 14) is driven to perform one full revolution. The

cam 24 xed to shaft 29, acting. through follower 2S and gears 23, 22, drives the cup disc 3 in mesh with the pinions and 5a, so that the tie beaks 26 and 27 perform mutually opposed rotations, thus reaching the respective positions illustrated in Fig. 2. During continued rotation the beaks 26, 27 pass yinto the position of Fig. 3 and form a loop in each yarn portion a, b. During further rotation of the tie beaks, the terminal ends c and d of respective yarn Ypieces a and b pass over and below respectively of the positionally xed yarn pieces a and b (Figs. 3 and 11), this being due to the different depths of the slots 6, 7 on the one hand and the slots 9, 10 (Figs. l2, 13) on the other hand.

Due to the fact that the tie beaks 26, 27 have in the Y meantime changed Vtheir rotational position, the knot loops are now ready to be stripped olf, and the yarn ends c and d are seized and held fast between respective'cheek 'and jaw members 50, 51 of the respective tie beaks 26, 27. During the subsequent stripping off of the loops, the knot is completed and the surplus ends of yarn are cut olf from the jaw members 51 and the cutting edges of 52. The stripping is effected by a motion of the tensioning member 17 which now moves axially and linearly between the two tie beaks to a protruding position in a direction to the left of beaks 26, 27, as viewed in Fig. 414. During this advancing motion the member 17 acts upon the yarn pieces a and b which is held between the slot 6 or 7, the yarn clamps 11, 12 and the tie beaks. Due to this action of member 17 the initially loose but completely looped lindividual knots are tightened and closed. The tie beaks now open and sever the ends c, d in conventional manner, 'as described, for example in German Patent 920,119. Thereafter the tension member 17 acts upon the yarn portions (Figs. 6 and 7) located between the tightened individual knots. Now the yarn pieces a and b can glide until their individual Aknots vapproach and touch each other (Fig. 8), thus forming the completed, knotted tie shown in Fig. 5.

The coaction of the individual operation described above is diagrammatically represented fin the graph of Fig. 15 where the abscissa denotes units of time t, the

i ordinate in the upper diagram portion denotes units of travel distance d, and the ordinate in the lower portion of the diagram denotes tensioning force F. The curve B indicates the travel motion of the tie beaks, the curve S the motion of the tension member 17, and the curve P the tension exerted by the member 17 upon the yarn.

The yarn pieces are placed in proper position during the time interval from t=0 to t=1. ln the time interval from l-5 there occurs the formation of the loops by means of the tie beaks as described above'and known as such, for example from German Patent No. 920,119. This loop formation is terminated att=5. Thereafter the tension member 17 moves beyond the tie beaks to such an extent that the yarn pieces are stripped off the tie beaks by forked arms 17a, 1719 and are thereafter slightly pulled, although at this stage the yarn ends to be tied together are not yet placed under heightening tension. This stage is apparent from Fig. 6 and shown on larger scale in Fig. 9. Between the time interval points t=6 and t=7, the tie beaks are moved back for a short interval of time and are simultaneously .opened so that the beaks are open at the time point 7 of the diagram (Fig. 7). In the meantime the tension member 17, at the time interval moment t'= 6, has reached its iirst step of motion when cam hump 30a (Fig. 14) reaches the cam follower 41 (at 130:1 in Fig. 15) and thus has tightened and closed the individual knots. Thereafter, after hump 30a passes the cam follower, the tension member 17 recedes a slight amount to the right (as viewed in Fig. 14) under the -action of spring 31. The tension curve P in Fig. 15 indicates accordingly that the tension first increases and then declines between the time points 6 and 7, the decline in tension being terminated before time point 7 is reached. After the opening of the beaks, namely between time points 7 and S, another forward motion is imparted to the tension member 17 vby hump 30b of cam 30 reaching cam follower 41, and this motion, shown at b of curve S (Fig. 5), now imposes a tensioning stress upon the tie connection. As a result the two individual knots approach each other, gliding along the yarn piece embraced by the individual loop of each knot (Fig. 8). At time point 9 the motion of the tension member 17 is terminated and the tensioning force P reaches its maximum value, which then during the subsequent receding travelof the tension member again declines down Vto zero. The knotted tie is now completed and is also tested by means of the tension member 17. The yarn is released from the knotter and the weaving, coil winding or other fabricating operation can be continued.

While knotting devices according to the invention are applicable in connection with textile fabricating machinery of various types, such devices are particularly favorable for use with automatic coil winding machines in which the yarn pieces to be tied extend from opposite directions toward the knotter, for-example, as shown and described in my U.S. Patent 2,733,870. By virtue of the loosening of the yarn pieces in the tie beaks prior to tensioning and tightening the connection, as afforded by the present invention, the occurrence of excessive stress in the yarn due to the knotting operation is prevented so that a repetition of the tying operation. is unnecessary in the great majority of cases.

It should be understood, of course, that the foregoing disclosure relates to only a preferred embodiment of the invention and that it is intended to cover all changes and modifications of the examples of the invention herein chosen for the purposes of the disclosure, which do not'constitute departures fromthe spirit and scope of the invention as set forth in the appended claims.

I claim:

l. A knotting device, particularly for forming a fishermans knot, comprising a housing, a cup member having a hollow shaft rotatably journalled in .said housing, first cam means operably connected for rotating said cup member one revolution when said device is actuated for operation, a plurality of rotatably` mounted beak members rotating in a first rotational direction and then clamping and subsequently releasing a respective one yarn end and forming therein an individual loop and knot passing around another yarn end, pinion means connecting said cup member with said beak Ymembers driving the latter in either direction, yarn tensioning means mounted for axial linear movement within said hollow shaft and operably movable relative to said beak members to strip said individual loops therefrom, second cam means operably joined in xed timed relationship to said irst `cam means, and lever means operably connecting said second cam means with said tensioning means for actuating the axial movement of the latter relative to said beak members, said first and second cam means having respective related cam surfaces, said cam surfaces actuating said beak members to release the yarn ends after said individual loop forming but prior to actuation of said tensioning member to pull said individual loop knots together.

2. A knotting device, particularly for forming a fishermans knot, comprising a housing, a cup member having a hollow shaft rotatably journalled in said housing,

first cam means operably connected for rotating said cup member one revolution when said device is actuated for operation, a plurality of rotatably mounted beak.

members rotating in a rst rotational direction and then clamping and subsequently releasing a respective one yarn end and forming therein an individual loop and knot passing around another yarn end, pinion means connecting said cup member with said beak members driving the latter in either direction, yarn tensioning means mounted for axial linear movement Within said hollow shaft and operably movable relative to said beak members to strip said individual loops therefrom, second cam means operably joined in xed timed relationship to said first cam means, lever means operably connecting said second cam means with said tensioning means for actuating the axial movement of the latter relative to said beak members, said first and second cam means having respective related cam surfaces, said cam surfaces actuating said beak members to perform a return rotational movement in opposition to said rst rotational direction subsequent to said releasing of said yarn ends by said beak members.

3. A knotting device, particularly for forming a fishermans knot, comprising a housing, a cup member having a hollow shaft rotatably journalled in said housing, first cam means operably connected for rotating said cup member one revolution when said device is actuated for operation, a plurality of rotatably mounted beak members each having respective cheek and jaw means rotating in a first rotational direction and then clamping and subsequently releasing a respective one yarn end and forming therein an individual loop and knot passing around another yarn end, pinion means connecting said cup member with said beak members driving the latter in either direction and for actuating said cheek and jaw means thereof, said cheek and jaw means including severing means for cutting off the protruding yarn ends, clamping means pivotally mounted outside of and engageable at one end thereof with said cup member wall, the other end of said clamping means being engageable with said yarn for clamping said yarn, yarn tensioning means mounted for axial linear movement within said hollow shaft and operably movable relative to said beak members to strip said individual loops therefrom, second cam means operably joined in xed timed relationship to said first cam means, lever means operably connecting said second cam means with said tensioning means for actuating the axial movement of the latter relative to said beak members, said first and second cam means having respective related cam surfaces, said cam surfaces actuat ing said cheek and jaw means to sever the yarn ends at least by the time said yarn tensioning member strips said individual loops from said beak members.

4. A knotting device according to claim 3 and including an eccentric cylindrical wall dispose around said cheek and jaw means of said beak members, said cy1indrical wall being positioned in timed relationship relative to said cam surfaces so as to open said cheek and jaw means subsequent to the looping and closing of the individual knots by said beak members.

5. A knotting device, particularly for forming a fishermans knot, comprising a housing, a cup member having a hollow shaft rotatably journalled in said housing, rst cam means and cam follower means drivingly connected for yrotating said cup member one revolution when said device is actuated for operation, a plurality of rotatably mounted beak members rotating in a first rotational direction and then clamping and subsequently releasing a respective one yarn end and forming therein an individual loop and knot passing around another yarn end, pinion means connecting said cup member with said beak members for driving the latter in either direction, yarn tensioning means mounted for axial linear movement within said hollow shaft and operably movable relative to said beak members to strip said individual loops therefrom,

second cam means operably joined `in xed timed relationship to said first cam means, second cam follower means including lever means operably connecting said second cam means with said tensioning means for actuatl ing the axial movement of the latter relative to said beak members, said second cam follower means having an adjustable member located in the force-transmitting path between said second cam means and said tensioning means for adjusting the force transmitted to said tensioning member from said second cam means;

6. A knotting device according to claim 5, said second cam follower means further including a resilient forcetransmission member located in the force-transmitting path between said second cam means and said tensioning means.

7. A knotting device according to claim 5, the length of said tensioning member, its movement relative to said beak members and said cam surfaces of said first and second cam means being mutually positioned and dimen sioned so as to linearly move said tensioning member relative to said beak members to first move the individual knots toward each other and subsequently to test the knotted tie by applying a predetermined tensile force thereto.

8. In a coil winding machine, a knotting device for forming a ishermans knot in yarn ends, comprising a housing, a cup member having a hollow shaft rotatably journalled in said housing, first cam means and cam follower means drivingly connected for rotating said cup member one revolution when said device is actuated for operation, the outer peripheral wall of said cup member having a toothed gear portion formed therein and further having a plurality of first yarn-receiving slots of respectively different depths relative to the brim of said cup member, a plurality of rotatably mounted beak members each having respective cheek and jaw means rotating in a first rotational direction and then clamping and subsequently releasing a respective one yarn end and forming therein an individual loop and knot passing around another yarn end, pinion means in meshing engagement with said toothed gear portion of said cup and with said beak members for rotating and for actuating said cheek and jaw means thereof, a plurality of stationary clamping members fixed to said housing and concentrically mounted relative to said cup member, each of said stationary clamping members having other yarn-receiving slots of respectively different depths formed therein and positioned for cooperating with said rst yarn-receiving slots to form a yarn-path through said cup member wall, movable clamping means comprising pivotablel lever means and abutment means, said lever means being pivotally mounted outside of and engageable at one endl thereof with said cup member wall, the other end of said lever means being engageable with said abutment means for clamping said yarn, yarn tensioning means mounted for axial linear movement'within said hollow shaft and operably movable relative to said beak members to pull said individual loops and knots mutually together and to strip said individual loops from said beak members, biasing means for normally urging said tensioning member in one predetermined direction, second cam means and second cam follower means operably joined in xed timed relationship to said first cam means, lever means linking said second cam follower means with said tensioning means for actuating the axial movement of the latter relative to said beak members in opposition to said 15 one predetermined direction, said first and second can means having respective related cam surfaces, said cam surfaces actuating said cheek and jaw means of said beak members to release the yarn ends after said individual loop forming but prior to actuation of said tensioning member to pull said individual loop knots together.

` References Cited in thele of this patent UNITED STATES PATENTS Abbott Dec. 2, 1941 2,723,871 Rudeen Nov. 15, 1955 FOREIGN PATENTS 920,119 Germany Nov. 11, 1954 

